Graham sent out a string of tweets Tuesday claiming the lack of response by the United States after the deadly attacks that killed four Americans invited aggression. This is what happens, he said, when Americans are killed and no one is held responsible. He added U.S. policy in Syria and Egypt has also proved Obama is a “weak indecisive leader.”

A number of Republicans, including Sen. John McCain (R-Ariz.) and Rep. Mike Rogers (R-Mich.), have been critical of the president as Russian troops took over the Crimean peninsula in Ukraine. They say U.S. foreign policy under Obama has emboldened Russian President Vladimir Putin.

The world is NEVER in a better place when you have a weak, indecisive American president. And Russia is a symptom of that weakness.

The White House has pushed back hard on the idea that Russia’s actions in Ukraine are coming from a place of strength.

“I actually think that this has not been a sign of strength but rather is a reflection that countries near Russia have deep concerns and suspicions about this kind of meddling, and if anything, it will push many countries further away from Russia,” Obama said Tuesday.